Jaw crusher with opposed jaws driven by unbalanced weights



Sept. 22, 1953 G. LINKE 2,652,985

JAW CRUSHER WITH OPPOSED JAWS DRIVEN BY UNBALANCED WEIGHTS Filed Sept.21, 1949 inrehfor: [fie/L1G! xinke/ Patented Sept. 22, 1953 UNITEDSTATES PATENT OFFICE JAW CRUSHER WITH OPPOSED JAWS DRIVEN BY UNBALANCEDWEIGHTS Gerhard Linke, Mulheim-Ruhr, Germany 6 Claims.

In the known stone crushing and pulverising apparatus the major part ofthe energy supplied is transformed into heat since the bodies to bepulverised slide under pressure in relation to one another and arethereby elastically or permanently deformed. Only a small part of thematerial is stressed to the breaking point and pulverised. This is to beascribed to the fact that during the impact together of the crusher jawsfrictional and crushing actions are mainly exerted on the material andnot the more favorable impact action. The mean speed of the crusher jawsamounts, in a normal jaw crusher, to about 10-20 cm. per second. Thisspeed is insufficient to achieve an impact action on the material.Consequently, the pulverising efficiency of these crushers is only verysmall. A comparatively large amount of energy is transformed uselesslyinto heat so that the power required is very high. In order to improvethe efficiency of the crusher, the crushing operation must be so carriedout that the bodies to be crushed do not lie close to one another in themouth of the crusher and that at each working stroke as few grains aspossible are subjected to impact at great speed. The mean speed of theoscillating crusher jaws should be about 35-60 cm. per second in orderto achieve a sufficient impact action. Jaw crushers are however known inwhich the mean speed of the crushing jaws is about 40-50 cm. per second,but the peak value of the acceleration in this construction does notexceed about 2.2 to 2.6 times the value of gravity. This constructiondoes not allow of a higher acceleration as the forces produced by theoscillating masses are not com pensated and the driving elements areunable to take up large acceleration forces. To achieve a sufficientefficiency of the crusher at these high impact speeds, it is howevernecessary that the time of oscillation and the time of fall of the grainheld between the crusher jaws and afterwards freed should bear adefinite relation to one another. The falling grain should meet thereturning crusher jaw at the moment when the jaw, after passing throughits outer dead centre, has already reached a substantial speed so thatthe grain is hurled by the crusher jaw into the mouth of the crusher.This results in the loosening of the material located in the mouth ofthe crusher and a travelling speed of the material through the mouth ofthe crusher sufficient for the high speed of oscillation. I

The invention is based on the recognition that time of oscillation andtime of fall, and therefore also the efliciency of the jaw crusher,reach favorable values when, at a mean speed of the oscillating crusherjaws of 30-60 cm. per second, the peak value of the acceleration is 3 to8 times the value of gravity. In the case where the space between thejaws is inclined, the lower values of the acceleration and speed are tobe preferred, while the higher values are to be preferred when the spaceis vertical.

The compensation of the oscillating masses in the jaw crusher accordingto the invention is conveniently achieved by having the two crushingjaws oscillate in opposed relation to one another and setting them inmotion by an out of balance drive whose unbalance wheels are journalleddirectly on the respective jaw structures. Such a drive makes itpossible to achieve a practically complete compensation of all forcesand moments and therefore the advantage that the time and stroke ofoscillation can be adjusted largely or wholly to suit the requirementsof the crushing operation without having to fear dis placement of thefoundation of the crusher. The oscillating cruhser jaws and the out ofbalance drive also relieve the housing of the crushing forces so thatthe construction can be made con siderably lighter than hitherto.

The use of the out of balance drive gives the further advantage that theforces necessary for moving the crushing jaws are applied directly fromthe unbalance wheels Where the greatest crushing forces occur. Thereserves of power necessary in every crusher are present in a sufficientdegree in the oscillating masses of the crushing jaws and of theunbalance wheels and in the rotating mass of the latter. No energy lossoccurs by energy flowing to and fro between the flywheel and crankdrive, or bell crank drive, as is the case in previous crushers.

The mechanical emciency of the drive can be still further improved byuse of resonance. It is advantageous to arrange the springs of thecrushing jaws so that their individual period of oscillation conformsapproximately with the operating period of oscillation. By asufficiently progressive characteristic of the springing and blind powerof the oscillating masses, a sufriciently constant stroke of theoscillating jaws can he achieved even with variations in the workingpower required so as to avoid impermissibly large variations in thecrushing space.

In order to regulate the speed of oscillation of the crusher jawssufliciently in accordance with requirements, the jaws are preferablyprovided with out of balance wheels which have a relative phasedisplacement of and which are connected with their fixed drive byelastic couplings. It is in this case particularly favorable when theout of balance wheels are mounted on the lower freely oscillating endsof the crusher jaws as here the maximum crushing forces occur.

A torque arises from the oscillation of the out of balance wheels withthe jaws. This can be compensated by spring suspension of the wholecrusher.

A further way of compensating torque is to pro vide each crusher jawwith two unbalanced wheels runnin in opposite directions which can becoupled together so that they have the same speed.

Furthermore, the torque can be compensated by providing additionalunbalanced wheels either at the pivot of the crusher jaws or outside thelatter. In the latter case an increase in crushing pressure can beachieved as well as compensation for the torque.

The drawings show examples of the invention.

Fig. l is a part-sectional side view of a jaw crusher, and Fig. 2 across-sectional top view of the same crusher, the section being takenthrough the plane determined by the axes of the two un-- balance wheelsof the machine.

Fig. 3 shows a schematic side view of the jaw portion and Fig. 4 is aschematic, part-sectional top view of another crusher.

Fig. 5 is a sectional view and Fig. 6 a partial side view of a jaw pivotand stop mechanism applicable in jaw crushers according to Figs. 1 and2.

In Figures 1 and 2 the two oscillating crusher jaws I and 2 aresuspended by their pivots it from the housing 4 of the crusher. The jawsI and 2 are maintained in their oblique position by springs 5, which areconnected at one end to the jaws and at the other to the housing 4. Eachjaw is driven by an unbalanced wheel 6, which is rotatably mounted onthe lower freely oscillating end of the jaw. The unbalanced wheels 6 ofthe two jaws I and 2 have their weights displaced in phase by 180.Rotary movement is transmitted from the fixed drive shaft 8 throughelastic couplings "I to the oscillating wheel 6.

The oscillating unbalance wheels 5 produce a force couple Pc (Fig. 1).Since this is undesired, means are provided for compensating for thiscouple. Accordingly, the crusher housing 4, with the jaws I and 2, theunbalance wheels 6, is hung on springs 23 so that the mass of the jawcrusher can execute a torsional oscillation about its centre of gravity.The amplitude of these oscillations is reduced by additional weights 2Ato a nondisturbing value. The additional weights 24 are preferablylocated as far as possible from the centre of gravity of the jawcrusher.

Spur gears l transfer the movement from the drive shaft 8' to the shafts9. Between the fixed drive shaft 8' and the gears Ii] is provided areversing spur gear II so that the two gears Ill and therefore the outof balance wheels 6 rotate in the same directions.

Instead of providing an out of balance wheel 6 on each of the crusherjaws I and 2, the couple Pc can be avoided by providing each jaw without of balance wheels I2 which rotate in opposite directions (Figs. 3and 4). These out of balance wheels l2. on each jaw I and 2 are coupledtogether by a spur gear drive I3. Between the fixed drive 8 and theelastic couplings I4, 2. fixed chain gear I can be used to transmit themovement to the out of balance wheels on the jaws l and 2. Instead ofthe chain drive I5, a gearing, corresponding to Fig. 2 may be used.

It is also possible to drive the out of balance wheels by electricmotors which are electrically synchronized in such a way that the speedsof rotation of the out of balance wheels are exactly equal and the phasedisplacement of the weights is maintained.

In order so to determine the springing of the jaw so that its own periodof oscillation agrees approximately with the period of oscillation ofthe jaws torsion rod springs I'I (Figs. 5, 6) are mounted on the jaws land 2. The torsion rods fastened by roller wedges in the housing 4 anddisposed within the hollow pivot 3. In the hollow of the pivot 3 thesprings I! are held by roller wedges I9. On the pivot 3 of each of thejaws I and 2 is provided a spring lever 20 which is attached to thepivot by a roller wedge 2| and due to the springing of the pivot,oscillates between two rubber buffers 22 fixed to the housing 4. Insteadof a special drive external to the crusher, a motor with its drivinggear may be mounted directly on the jaws I and 2 to move with them. Thesupply of material to be crushed can be so regulated by an oscillatingdischarge device that overfilling of the mouth of the crusher isprevented. The crusher is conveniently connected in circuit with ascreening device so that the grain size of the crushed materialcorresponds to desired requirements.

What I claim and desire to secure by Letters Patent is:

1. A jaw crusher, comprising two jaws pivoted for oscillation inopposition to each other, unbalance wheels having wheel bearings rigidlymounted on said jaws remote from the respective jaw pivots to oscillatetogether with said jaws, said wheels having respective unbalance weightsphase displaced relative to each other, a stationary drive, and elasticcoupling means conmeeting said drive with said wheels.

2. A jaw crusher, comprising stationary supporting structure, a crusherhousing elastically suspended from said structure to be capable ofoscillatory motion relative thereto, two crusher jaws each having oneend pivoted on said housing for oscillatory movement in opposingrelation to corresponding movement of the other jaw, unbalance wheelshaving respective bearing means rigidly mounted on said jaws near theoscillatory ends respectively of said jaws, said wheels havingrespective unbalance weights 180 phase displaced relative to each other,a drive stationary with respect to said structure, and elastictransmission means connecting said drive with said unbalance wheels.

3. A jaw crusher, comprising a spring-suspended housing, two crusherjaws each having one end pivoted on said housing for pivotal oscillationin opposition to the other jaw, unbalance wheels having respectivebearing means rigidly mounted on said jaws near the oscillatory endsrespectively of said jaws, said wheels having respective unbalanceweights 180 phase displaced relative to each other, a stationary drive,elastic coupling means connecting said drive with said wheels, andadditional weights disposed on said crusher housing for minimizingtorsional oscillations of the crusher.

4. A jaw crusher, comprising two jaws pivoted for angular oscillationin, opposition to each other, two first unbalance wheels each havingbearing means rigidly mounted on one of said respective jaws near theoscillatory jaw end and having an unbalance weight 180 phase displacedrelative to the unbalance weight of the first unbalance wheel on saidother jaw, two second unbalance wheels each having bearing means rigidlymounted on one of said respective jaws, spur gear means coupling saidsecond unbalance wheel of each jaw with said first unbalance wheel ofthe same jaw for rotating them in opposition to each other, stationarydrive, and elastic transmission means connecting said drive with saidunbalance wheels.

5. A jaw crusher, comprising a housing structure, two opposinglyoscillating jaws having respective hollow pivots revolvably pivoted onsaid structure for oscillation in mutually opposing relation, unbalancewheels having respective bearing means rigidly mounted on saidrespective jaws remote from the respective jaw pivots to oscillatetogether with said jaws, said wheels having respective unbalance weights180 phase displaced relative to each other, a stationary drive connectedwith said wheels, and torsion rod springs disposed within saidrespective hollow pivots, each spring having one rod end secured to oneof said respective jaws and having the other rod end secured to saidstructure.

6. A jaw crusher, comprising a housing structure, two opposinglyoscillating jaws having respective hollow pivots revolvably pivoted onsaid structure for oscillation in mutually opposing relation, unbalancewheels having respective bearing means rigidly mounted on said jawsremote from the respective jaw pivots to oscillate together with saidjaws, said wheels having respective unbalance weights 180 phasedisplaced relative to each other, a stationary drive connected with saidwheels, and torsion rod springs disposed within said respective hollowpivots, each spring having one rod end non-revolvably secured to one ofsaid jaws, two lever arms having pivot axes substantially coaxial withsaid respective springs and being joined with the other endsrespectively of said springs, and two pairs of mutually spaced buffersof elastically compressible material mounted on said housing structure,each of said lever arms extending between the two bufiers 01 one of saidrespective pairs.

GERHARD LINKE.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 472,367 Knapp Apr. 5, 1892 1,491,430 Stebbins Apr. 22, 19241,936,742 Youtsey Nov. 28, 1933 2,170,768 Schieferstein Aug. 22, 19392,352,970 Pollitz July 4, 1944 FOREIGN PATENTS Number Country Date219,137 Germany Feb. 17, 1910 306,017 Germany June 11, 1918 515,819Germany Jan. 13, 1931 52,728 Norway June 26, 1933 727,417 Germany Nov.3, 1942 OTHER REFERENCES Serial No. 372,589, Bachmann (A. P. C.),published May 4, 1943.

